The pilot reported that the airplane veered sharply to the left when he applied the brakes during the landing roll on a grass airstrip. He applied right rudder to no avail and the airplane continued to the left where the left wing contacted a corn crop. The airplane was pulled into the corn where it came to rest with substantial damage to both wings and the aft fuselage. The pilot reported the airplane’s brakes operated normally prior to takeoff. The brake system consists of main landing gear hydraulic disc brakes which are operated via a mechanical brake lever located on the control stick. The airplane has a steerable nosewheel, but no differential braking. A postaccident inspection of the airplane revealed that hydraulic fluid was present in the brake system. Both brakes functioned when the brake lever was operated, however; the left brake responded quicker than the right brake.